RichieC wrote:
A VOM is well worth learning to use, BUT if you don't use it all the time or don't have the desire for it you may find yourself unsure of your ability to use it.
As suggested, use a polarity tester to back up your diagnoses.
I would also suggest you get a Non Contact Voltage Tester (NCVT) to confirm the outlet isn't miswired as a Reverse Polarity Bootleg Ground (RPBG). There are no outlet testers on the market that can discover an RPBG. See my article on Gary Bunzer's newsletter about how to use a NCVT to check for this dangerous condition
RV Doctor And here's how to use a NCVT to check for outlet polarity and RV hot-skin conditions
Hot-Skin TestMike Sokol
www.NoShockZone.org